Field of the Invention
The present invention relates to a display device and a method of controlling the same.
Description of the Related Art
One scheme for achieving high-contrast display in liquid crystal display devices is the dual-layer LCD technology. The dual-layer LCD technology considerably improves the contrast by superimposing two liquid crystal panels, relative to a structure using one liquid crystal panel.
In the dual-layer LCD technology, space is often provided between the liquid crystal panels upon arranging liquid crystals into two layers, in order to prevent scratches or the like caused by contact of the liquid crystal panels. Even without the space being provided between the liquid crystal panels, space due to the thickness of the liquid crystal panel itself exists. With the influence of the space, there are cases where images displayed in same positions on the two liquid crystal panels appear to be in differing positions, depending on the angle (direction) of observation in which a user views the images. This phenomenon is particularly significant with high-frequency images of a string of characters, numbers, or the like in which a difference in tone is distinct. This poses a problem of low visibility due to the characters or numbers appearing as a double image.
As a method of solving the problem, technology is disclosed in which a light-transmitting area of an LCD on the backlight side contains a display area for input image signals so that a decrease in visibility is prevented regardless of the direction of observation. Related art of the present invention is described, for example, in Japanese Patent Application Laid-open No. 2010-14989 and Japanese Patent Application Laid-open No. 2013-130841.